i went to my dentist and consulted re teeth whitening.
this costs 7k. she made a mould sa akong teeth and then gave me three tubes of this whitening substance that appears like gel. i inject monggo-size volume of the gel in the slots for the teeth. i wipe my teeth dry before putting on the mould with the gel. they stay on overnight. it makes the teeth sensitive but it works.
to save on the gel, i use it every other day.
when i brush my teeth, i dip my toothbrush bristles in baking soda before squeezing out the toothpaste on the bristles.
this works.